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Please help! Math question.

Please help! Math question.-example-1

2 Answers

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It’s it’s the fits the first one
User Monsters X
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When solving inequalities, you can treat it like you would an equation with an equal sign. However, remember that whenever you multiply or divide by a negative number, you must flip the inequality sign.

You're given
(-ax)/(b) \geq c -d and asked to solve for x:
1) Multiply both sides by b

(-ax)/(b) \geq c -d \\ -ax \geq b(c-d)

2) Distribute the b to the c and d using the distributive property

-ax \geq b(c-d)\\ -ax \geq b(c)-b(d)\\ -ax \geq bc-bd

3) Divide both sides by -a. Don't forget to flip the inequality sign!

-ax \geq bc-bd\\ x \leq (bc-bd)/(-a)

4) Simplify by multiplying the right side by
(-1)/(-1) (aka 1) to get rid of the negative on the a.
You don't need to flip the sign here (think of it as dividing and the multiplying by -1, so you flip it twice, which is the same as not flipping at all!)

x \leq (bc-bd)/(-a) \\ x \leq (bc-bd)/(-a) ( (-1)/(-1) )\\ x \leq (-bc+bd)/(a) \\ x \leq (bd-bc)/(a)

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Answer: Top right,
x \leq (bd-bc)/(a)


User Charlie Vieillard
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